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The purpose of this paper is to provide a source of information on thermal energy use in buildings, its drivers, and their past, present and future trends on a global and regional basis. Energy use in buildings forms a large part of global and regional energy demand. The importance of heating and cooling in total building energy use is very diverse with this share varying between 18% and 73%. Biomass is still far the dominant fuel when a global picture is considered; the role of electricity is substantially growing, and the direct use of coal is disappearing from this sector, largely replaced by electricity and natural gas in the most developed regions. This paper identifies the different drivers of heating and cooling energy demand, and decomposes this energy demand into key drivers based on a Kaya identity approach: number of households, persons per household, floor space per capita and specific energy consumption for residential heating and cooling; and GDP, floor space per GDP, and specific energy consumption for commercial buildings. This paper also reviews the trends in the development of these drivers for the present, future – and for which data were available, for the past – in 11 world regions as well as globally. Results show that in a business-as-usual scenario, total residential heating and cooling energy use is expected to more or less stagnate, or slightly decrease, in the developed parts of the world. In contrast, commercial heating and cooling energy use will grow in each world region. Finally, the results show that per capita total final residential building energy use has been stagnating in the vast majority of world regions for the past three decades, despite the very significant increases in energy service levels in each of these regions. ; The work is partially funded by the Spanish Government (ENE2011–28269-C03-02 and ENE2011-13511-E). The authors would like to thank the Catalan Government for the quality accreditation given to their research group GREA (2014 SGR 123) and research group DIOPMA (2014 SGR 1543)

This paper aims to complete and complement the information available on the past trends of thermal energy consumption in residential buildings and its drivers for Europe, as a continent and for the different countries. This paper follows the drivers identified in a previous one for the heating and cooling energy consumption, decomposing this energy demand into key drivers based on a Kaya identity approach: number of households, persons per household, floor space per capita and specific energy consumption for residential heating and cooling. Results show that all drivers did follow a consistent trend at global, regional and country level during the studied period of time, but the heating and cooling energy consumption did not follow the same trend if it was considered at global, regional or country level, showing that the energy consumption is very much influenced by all its drivers and does not follow the same trend as the specific energy consumption. Moreover, similar trends for each indicator can be found when evaluated at country or regional level, therefore as expected when aggregating data trends can be seen but details and particularities (both for the different countries and for the different studied years) are lost. ; The work is partially funded by the Spanish government (ENE2015-64117-C5-1-R (MINECO/FEDER)). The authors would like to thank the Catalan Government for the quality accreditation given to their research group GREA (2014 SGR 123) and research group DIOPMA (2014 SGR 1543). Dr. Camila Barreneche would like to thank Ministerio de Economia y Competitividad de España for Grant Juan de la Cierva, FJCI-2014-22886.

This paper deals with an effect which appears when heating or cooling a rotating body. No external forces acting on the body are supposed. Due to thermal expansion, the moment of inertia of the body varies together with the temperature changes. In agreement with the principle of conservation of angular momentum [1], the angular momentum is constant. This results in angular velocity changes and subsequently in kinetic energy changes. Also the stress energy varies together with the changes in thermal dimension. To satisfy the principle of energy conservation we have to suppose that the changes in kinetic and stress energy are compensated by the changes in internal energy, which is correlated with temperature changes of the body. This means that the rules for the heating or cooling process of a rotating body are not the same as those for a body at rest. This idea, applied to a cylinder rotating around its geometric axis under specific parameters, has been mathematically treated. As a result, the difference between the final temperature of the rotating cylinder and the temperature of the cylinder at rest has been found.

The basic issue of this thesis concerns one of the fundamental problems of the future of our society: How to meet the energy requirements for a large and growing world population while preserving our environment? This question is important for the world and the answers are complex and interwoven.Conventional energy sources, fossil and fissile, are polluting in the present and in the future: they erode the environment and their resources are limited. Renewable energy (hydro, wind, solar, geothermal) constitutes a minimum of pollution in the different energy systems. The technologies for using renewable energy are well known though further development and progress are made. This development also requires behavioural change, adaptation, and above all political will. The transition from an economy based on fossil energy to an economy based on renewable energy appears necessary for the protection of the environment. The cost of renewable energy is often represented as an obstacle but remains competitive in the long run.The development and availability of renewable energy, which varies because of its spatial and temporal distribution, require an adaptation of lifestyle, habits, habitat design (passive bioclimatic houses), urban planning and transportation.The focus of this thesis was to apply renewable energy in an area with hot summers and cold winter, a climate like that in the northwest of Algeria. In order to provide improved comfort in the buildings and also economic development in this area, the energy demand for heating and cooling was analyzed in the ancient city of Tlemcen. To supply domestic hot water and space heating, water must be simultaneously available at two different temperature levels. Cold water temperature, close to that of the atmosphere, and hot water between 50 and 60°C. An interesting feature of the preparation of hot water is the small variation of requirements during the year, unlike that to heating. The preparation of hot water is one of the preferred applications of solar energy in the building for several reasons. For this reason an experimental study of the thermal behaviour of a domestic hot water storage tank was undertaken. The phenomena that affect the thermal behaviour of tank especially the coupling between the solar collector and storage tank was studied. This study included concentrating solar collector in which optical fibers were used to transport the energy to the storage tank. Another technology was introduced and developed for the heating and cooling of buildings in the desert involving an existing ancient irrigation system called Fouggara. The novel idea is to use the Fouggara as an air conditioner by pumping ambient air through this underground system. Then air at a temperature of about 21°C would be supplied to the building for heating in the winter and cooling in the summer. This study shows the feasibility of using this ancient irrigation system of Fouggara and contributes to reducing and eliminating the energy demand for heating and cooling buildings in the Sahara desert. ; Godkänd; 2011; 20110920 (sofama)

In Europe, there is a long-term objective to decarbonise the energy system, but it is currently unclear how this will be achieved for heating and cooling (H&C) demand of residential buildings. The European project "Heat Roadmap Europe" aims to develop low-carbon heating and cooling strategies, by quantifying changes at the national level for 14 EU member states. One aspect of such strategies is the refurbishment of the existing building stock and the associated costs and energy savings. Therefore, cost curves of reducing the H&C demand in residential buildings are calculated, based on the FORECAST group of models. To estimate the investment costs for additional savings compared to a baseline development, this model framework includes refurbishment measures per building element (e.g. walls, windows, etc.). By ranking the refurbishment measures according to their specific cost and energy saved, one can derive annualized cost curves. Such curves have been widely used as a decision support tool by showing the additional costs or investment needed for a certain additional amount of energy- or CO2 savings on a national scale. The analysis shows that supporting deeper thermal renovation of buildings which undergo renovation under baseline considerations, is the most important missed opportunity to further reduce H&C demand. This can be achieved by e.g. converting overhaul of buildings into energy efficient retrofit or to include additional building elements in a planned partial retrofit. Further savings can be achieved by increasing the refurbishment rate (i.e. doing renovations in buildings which are untouched in the baseline). Beyond certain thresholds, however, additional policy efforts would be needed to e.g. convince investors to aim for respective measures. Addressing these options needs more long-term oriented changes in the investment behaviour but it may be needed to achieve the full potential of additional energy savings. The project Heat Roadmap Europe (4) has received funding from the European Union's Horizon 2020 research and innovation programme and the Swiss Federal Office for Research and Innovation under grant agreement No 695989.

VTT Tiedotteita - Research Notes 2256 ; This Summary Report summarises and presents the contents of the Guidebook, which is included here in CD-ROM format. The Guidebook is meant to help engineering offices, consultants and architects in their search for energy efficient heating and cooling systems that can provide the occupants with comfortable, clean and healthy environment. In addition, some background information is offered for real estate builders, building maintenance managers, political decision makers and the public at large. The Guidebook is available as a CD-rom version and also freely available on the internet (http://www.lowex.net/). Exergy defines the quality of energy and is an important tool for designing and assessing different heating and cooling systems. In Annex 37, 'low exergy(LowEx) systems' are defined as heating or cooling systems that allow the use of low valued energy as the energy source. In practice, this means systems that provide heating or cooling energy at a temperature close to room temperature. Low temperature heating systems or high temperature cooling systems that are suitable for office buildings, service buildings and residential buildings, can use a variety of fuels and renewable energy sources. These systems use energy efficiently while providing a comfortable indoor climate. They should be widely implemented now in order to create possibility to use sustainable energy sources in the near future.

This article discusses the lack of integrated renewable heating and cooling policy in the United States in light of the Obama Administration's proposed energy and climate strategies. The article argues that renewable heating and cooling will be a necessary component of future climate mitigation and fuel diversification strategies in the US, and surveys emerging state-level renewable heating and cooling policies as potential models for future policy development.

This report describes research that has been conducted for the Monash Buildings and Property Division with support received from the Victorian Government Microgrid Demonstration Initiative. Behaviourworks Australia undertook a field trial with the aim of gaining a better understanding of occupants experience of potential alterations to the control of building heating and cooling systems and their behavioural response under microgrid test conditions.

This report describes research that has been conducted for the Monash Buildings and Property Division with support received from the Victorian Government Microgrid Demonstration Initiative. Behaviourworks Australia undertook a field trial with the aim of gaining a better understanding of occupants experience of potential alterations to the control of building heating and cooling systems and their behavioural response under microgrid test conditions.

International audience ; By 2020 all new buildings within the European Union should reach nearly zero energy levels. Their energy needs should be significantly covered by renewable energy sources. As a consequence, it is important to identify which combinations of technologies will be suitable in order to reach such objectives. Climate conditions, final energy and investment costs, technological maturity and stakeholders' services quality are key elements for the final choice. This paper presents the first results of a more general survey the purpose of which is to study different combinations of heating-cooling systems integrated in single-family dwellings under the Belgian climate conditions. Eight representative dwellings and one heating system composed of solar collectors and an air-to-water heat pump were selected. The dwellings were chosen in such a way that different insulation levels may be studied: we considered houses with an insulation level that just respects the 2008 EPBD legislation (arête du gouvernement wallon, 2008) as well as very low energy houses. The heat pump and solar collectors are connected to a heat storage water tank as well as to a DHW reservoir. A design procedure based on energy needs is proposed and applied to each dwelling-system. The design characteristics of the system are then integrated in a simulation software (TRNSYS 17) to perform a one-year energy performance calculation (Klein, S.A, et al.,2000). The results show that the solar coverage ratio for DHW production ranges from 52% (very low energy buildings) to 76% (EPBD buildings). The solar coverage ratio for space heating ranges from 3% (very low energy buildings) to 9% (EPBD buildings). Whatever the kind of building, the seasonal performance factor of the heat pump is about 3.45. The total non renewable primary energy that is used is about 57% of the total heat demand.

In the context of developing a low-carbon economy by 2050, the European Union (EU) member states have committed to improve energy efficiency by at least 27% by 2030. To empower municipalities and local authorities addressing this goal, the H2020 PLANHEAT research project develops an open-source software tool for developing economically sustainable energy plans for low-carbon heating and cooling. To take into account the Urban Heat Island (UHI) effect on energy demand, the PLANHEAT software tool uses a geospatial dataset of hourly 1 km Heating and Cooling Degrees that is derived from satellite thermal data and information from weather models. This article describes the methodology used for producing this dataset and presents the first results for the city of Antwerp in Belgium. The PLANHEAT tool will be released as a QGIS plugin in June 2019.